1. Field of the Invention
The present invention relates to a single or multi-wire welding torch which can be connected to a welding device via a hose pack and consists of several components such as a torch handle, a tubular welding torch housing, a contact tube for each welding wire, a gas nozzle, etc., wherein an internal insert for receiving said one or more contact tube(s) and said gas nozzle is mounted in an end area of said welding torch housing. The present invention also relates to a laser-hybrid single or multi-wire welding head wherein components such as a laser or a laser lens system, a crossjet and welding torch components for arc welding are provided on at least one mounting element, said components being connected to a laser beam source and a welding device for melting wire welding processes via leads. Moreover, the present invention relates to a single or multi-wire welding torch, e.g. for laser-hybrid welding, having components for arc welding with melting welding wire, with said one or more components being formed by a contact tube having a throughout guiding bore having a longitudinal central axis to guide each welding wire. Furthermore, the present invention relates to a method for the process control of a robot welding system having a control device and a welding torch, particularly for laser-hybrid welding, mounted on a robot arm, said welding torch being provided with a gas nozzle in the area of a welding wire exit.
In addition, the present invention relates to a gas nozzle for a welding torch, particularly for a laser-hybrid welding head, having a tubular housing with an exit opening for a welding wire and, opposite, a receiving area for mounting on an internal insert of said welding torch, and it also relates to a gas nozzle for a multi-wire welding torch having a number of contact tubes, particularly for a laser-hybrid welding head, said gas nozzle having a tubular housing extending along a central longitudinal axis and having an exit opening for a welding wire on a first front surface and, opposite, on a second front surface a receiving area for mounting on an internal insert of said welding torch.
2. Description of the Related Art
Welding devices and welding processes for melting electrodes, e.g. MIG/MAG welding processes, are known from prior art. Systems and processes for welding using laser beams are known, too. Combinations of these processes, known as laser-hybrid processes, using appropriate devices are also known and widely used.
For example, prior art devices for laser-hybrid welding processes are known from WO 02/40211 and WO 01/38038. These welding devices, however, have some disadvantages, primarily when using multi-wire welding torches, because the gas nozzle does not take into account the special conditions arising from the use of multiple welding wires with respect to torch distance, stick-out lengths, etc. This may cause problems for welding process control.
Such known welding devices are used intensively in the automated production industry in the form of computer-controlled robot welding systems. In such systems, the welding torch is guided along the points of connection on a work piece by a robot arm. The welding process produces depositions on the gas nozzle and the contact tube of the welding torch in the welding wire exit area caused by welding spatters, contact welding between welding wire and contact tube, etc. Therefore, it is necessary to regularly maintain and clean the welding wire exit area of the welding torch to ensure the welding process to proceed undisturbed. For maintenance, the contact tubes, which provide an electric connection to the welding wire, and optionally further parts, e.g. the gas nozzle, are manually exchanged by maintenance personnel. Such personnel have to dismount the usually screwed-in contact tubes and the screwed-on gas nozzle one by one and remount the new ones. This has proven very disadvantageous and costs a lot of money and time, because it requires entire production lines to come to a standstill.